A known device for extracorporeal blood treatment comprises at least one treatment unit such as a dialyzer and, respectively, a dialyzer device, or a filter, ultra-filter or plasma filter of a different filter unit having a semipermeable membrane for separating the treatment unit into two chambers. An extracorporeal blood circulation enables blood taken from a patient to flow through the first chamber back to the patient. At the same time, in the opposite direction thereto a dialysis fluid (treatment fluid) flows through an appropriately designed circuit via the second chamber. The known device moreover includes a dialysis fluid line for fresh dialysis fluid connected to the second chamber on the inlet side and a dialysis fluid line for used dialysis fluid connected to the second chamber on the outlet side.
After the end of therapy and the return of blood, the user of the known device usually is confronted with the problems of an appropriate draining of the (fluid) system of the device. With respect to draining, so far merely a cartridge possibly used during therapy, for example a bicarbonate cartridge, as well as the dialyzer device (the dialyzer) on the water side have been supported so far. The blood side, on the other hand, usually remains filled. This involves risks of infection and unnecessarily increases the amount of weight of disposables such as of the dialyzer and the blood hose system. Moreover, even when the user exercises utmost care, regularly blood residues and/or residual components of fresh and/or used dialysis fluid reach the surrounding bottom surface and/or to the device and, respectively, the machine itself.
Known methods and/or devices in general include flushing of the hose system with a liquid such as e.g. saline solution or dialysis fluid so as to remove residual blood and draining of the flushing liquid through a specific outlet.
As a rule, a user is provided with description and training as to how a device or a machine for extracorporeal blood treatment has to be dismounted again after therapy. Accordingly, merely the water side of the system and the cartridge are drained, however. It is not taken into consideration, however, in which way blood-side residual amounts in the blood hose system have to be treated. However, residual or waste amounts which are annually accumulating on the blood side and have to be disposed cost-intensively as special waste are considerable.
Hence there is a need of a solution which also assists the user equally fully automatically in draining (on the blood side) the hose system including the dialyzer just as in draining the system and the cartridge (on the water side).